2022 Volume 39 Issue 4 Pages 562-566
We present a case of 76-year-old man with a medical history of laryngeal cancer, rectal cancer, and rheumatoid arthritis. Two weeks before the first visit, a reddish tumor appeared on his left abdominal skin, and he was referred to our department. Indurated erythema was observed with a major axis of 5 cm on the left abdominal skin, and a hemispherical dark reddish tumor was noted with a major axis of 2 cm on the erythematous lesion. Histopathological examination of skin biopsy revealed large, well-defined atypical cells with nucleoli proliferating throughout the dermis. Immunostaining revealed positive findings for CD4, CD56, CD123, and TCL1, and we diagnosed the patient with a blastic plasmacytoid dendritic cell neoplasm. CHOP chemotherapy was performed. It was initially effective for the skin lesions, but gradually became refractory to treatment. Over time, many reddish tumors and indurated erythema appeared on the trunk and limbs. Radiation therapy performed for the skin lesions was effective in local control. Although this disease is extremely rare, it is a fatal disease that transfers to the leukemic phase at a high rate. Most cases develop from skin lesions, so dermatologists should be able to recognize this entity. In general, radiation therapy for blastic plasmacytoid dendritic cell tumors is effective in local control of skin lesions, although it does not contribute to prolonged prognosis.
